Electric plug or socket extension.



No. 702,535. PATENTED JUNE 14, 1904.

` w. H. KELSEY.

ELECTRIC PLUG 0R SOCKET EXTENSION. APPLIGATION FILED 0010, 1902. 11011011111.. a sums-01111111 1.

II'IIIIIIIIIII 'fr' il' l YIIIIIIIIIIIIIIIIII WJLQEEE5 y I IrlErfLmQl/a*WWW* Mf@ il g No. 762,535. PATENTED JUNE 14, 1904.

` W. H. KELSEY.v

ELECTRIC PLUG 0R SOCKET EXTENSION.

APPLIUATION FILED 00T. 9, 1902.

3 SHEETS-'SHEET 2.

N0 MODEL.

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No. 762,535. PATENTED JUNE 14, 1904. W. H. KELSEY.

lELECTRIC PLUG OR SOCKET EXTENSION.

, vAPPLICATION FILED oom-.9. 1902.' No MODEL. 3 sHnnTs-sHEET s.

Riverina/gag'- 00%"i m7/ v Y Patented June 14, 1904.

PATENT OFFICE.

WILLIAM H KELSEY, OF CAMBRIDGE, MASSACHUSETTS.

ELECTRIC PLUG OR SOCKET EXTENSION.

SPECIFICATION forming part of Letters Patent No. 762,535, dated June 14,1904.

Application iilell October 9, 1902.

T0 all whom 7115 may con/cern:

Be it known that I, WILLIAM H. KELsEIQof Cambridge, in the county ofMiddlesex and State of Massachusetts, have invented certain new anduseful Improvements in Electric Plug or Socket Extensions, of which thefollowing is a specication.

This invention relates to improvements in socket and plug extensions,designed more especially as a portable or removable fixture to be usedin connection withan electric socket or plug and to provide'meanswhereby a plurality of lamps or other devices using electricity may bedetachably attached tothe device, and whereby the style of the socketsand plugs on the extension may dier or may be the same as the socket orplug to which the extension is to be attached, and whereby the varioussockets and plugs on the .extension itself may be of the same or ofdifferentstyles.

The invention has for its object to .provide a novel socket or plugextensionwhich shall be neat, convenient, easilyrapplied, and simple inconstruction, therefore notliable to get out of order, and also toprovide means whereby lamps or other. devices requiring electricity ofthe same or of different potentialsmay be used and arranged in series orin parallel.

The invention consists of the novel constructions, arrangements, andcombinations of parts, as fully described hereinafter and claimed, andit is carried out substantially as illustrated on the accompanyingdrawings, which form an essential part of this speciiication, andwhereon- K Figure 1 represents a side' elevation of my improved socketVor'plug extension arranged as a portable chandelier. Fig.A 2 representsa detail longitudinal section of the upper end of the device as shown.in Fig. l and showing the arrangement of a preferred form of socket onthe ceiling, to which the extension is attached. Fig. 3 represents adetail longitudinal section of the lower end of the device as shown inFig. l, showing a socket therein adapted to receive the plug end of anelectrically-operated device to be attached thereto. Fig. 4 represents adetail section showing one of thc manners of running the electricconductors Into a. branch of the main cas- Serial No. 126,630. (Nomodel.)

ing. Fig. 5 represents a detail section showing another manner whereby acurrent of electricity may be conducted into and from a detachablebranch casing from and into the main casing. Fig. 6 represents a planview of another arrangement of my improved socket and plug extension,which is arranged to be attached to an electric socket and to receivethe connecting plug ends of several different electrically operateddevices and whereby the connections between the receiving-sockets forsuch plug ends are such that said devices may be arrangedin series, inparallel, or in a combination of series and parallel or in all of saidarrangements as desired. Fig. 7 represents a central longitudinalsection of the device shown in Fig. 6 on the line A B on said Fig. 6.Fig. 8 represents a central longitudinal section of the same device onthe line C D in Fig. 6. Fig. 9 represents a cross-section of the deviceon the line E F in Fig. 7 Fig. 10 represents a cross-section of thedevice on the line G Hin Fig. 8, also showing a section of another formof my improved device attached thereto, whereby the device may boadapted to be attached to an electric socket of a style differing fromthose contained therein. Fig. 11 represents a plan View of anotherarrangement of my improved socket and plug extension, which is arrangedto receive the connecting plug ends ofthe several differentelectrically-operated devices and whereby the connections between thereceiving-sockets for said plug ends are such that any one or all ofsaid sockets may be used and when used will be arranged in multiple withthose in the other sockets. Fig. 12 represents a sectional sideelevation of the extension shown in Fig. 1I. Fig. 13 represents acentral longitudinal section of the extension ou the line I J in Fig.

IOO

and 16. Figs. 19 and 2O represent, respectively, a central longitudinalsection and an end view of one of the plug ends which may be used inconnection with the socket shown in Figs. 17 and 18. Fig'. 21 representsthe preferred manner of forming the electric conductor used within thesocket extension to connect and hold one or more of the sockets usedtherein and showing the same in plan view prior to bending the same intothe .shape it assumes when within the socket extension.

Like characters of reference refer to like parts wherever they occur onthe different parts of the drawings.

On the drawings in the principal views thereon I have shown myinventionarranged as a detachable 0r portable socket and plug extension to beused in connection with Edison sockets and fixtures, and consequently7have provided the extension with what is known in the trade as Edisonplug ends and sockets wherever such are used; but itwill be understoodthat plug ends and sockets such as the Thomson-Houston, Swan, or of anyother make might be used in lieu of those shown.

In Figs. 1 to 5, inclusive, I have illustrated myimproved socketextension arranged as a` portable chandelier. In this construction Iprovide the upper end of the extension with a plug end by which theextension may be attached to a suitable socket which is permanentlyattached to the wall or ceiling of a room or other place where theextension is to be used. rlhe plug end shown at the upper end of thesocket extension consists of the outer screw-threaded shell 1, whichforms one electric terminal of the plug end, and the metal piece 2,which forms the opposite terminal of such plug end. The main part` ofthe easing of the extension consists of a tubular portion 3 and hasattached thereto one or morebianch arms 4, which may be permanently ordetachably attached thereto, as may be desired and as will be understoodbythe complete description of the extension hereinafter contained.

To the upper end of the tubular portion 3 of the casing is attached theplug end by which the extension is attached to the socket when desiredand it is necessary that the electric terminals in this plug end shouldbe insulated from the casing 3. On the drawings the plug end has beenshown as being provided with the frame portion 5, made of insulatingmaterial and provided with flanges which in connection with a ring 6,screwed on the screwthreaded end of the tubular casing 3, firmly securesthe plug end to the tubular portion 3 of the casing. The metal piece 2,which forms one electric terminal on the plug end, is made upon the endof a rod 7, which passes through a perforation in the frame portion 5 ofthe plug end and hasitsinnerscrew-threaded end screwed into a block 8within the tubular portion 3 of the casing. Conductors or wires 9 and 10are attached, respectively, to the shell 1 and to the block8,*and-therefore are in electrical connection with the respectiveterminals 1 and 2 of the plug end and by which a current of electricitymay be conducted between such terminals and the interior of the tubulareasing. If permanently-connected arms 4 are to be used so as to radiatefrom the tubular casing 3, I prefer to run the conductors from thecasing directly into the arms, and vice versa, substantially as shown inFig. 4; but when the arms 4 are to be made detachable andinterchangeable with other arms I prefer to provide the casing 3 with asocket or plug at the place where the arm iste be attached and toprovide the arm4 with a socket or. plug which may be connected to thesocket or plug in the casing, so as to properly and electrically connectthe conductors in the arm to those in the casing, and thereby conduct acurrent of electricity into and from the arm 4 and substantially asshown in Fig. 5. In Fig. 4 the arm 4 is screwed into a screwthreadedperforation 11 in the main casing 3,

and the conductors 12 and 13 run between the interior of the casing 3and the interior of the arm 4. In Fig. 5 the arm 4'is detachablyattached to acollar or sleeve 14, screwed into a screw-threadedperforation in the casing. I/Vithin the casing 3 is a block 15,preferably made .of insulating material, as porcelain, and held inposition within the casing 3 by two or more of the sleeves 14, whichradiate from the center of the casing. To the block 15 is secured theinternally-screw-tlneaded metallic shell 16, which forms -the electricsocket to receive the plug end contained within the arm to be attachedat this place. Between the shell 16 and the block 15 is placed aringshaped plate or washer 17, having ends projecting from the sides ofthe same, and to said ends at opposite ends of the block 15 are attachedthe conductors 18 and 19. It will thus be seen that there is an electricconnection between the conductor 18, the shell 16, and the conductor 19.It will be understood that a number .of shells 16, with attachedconductors 13 and 19, may be arranged upon the block 15 so as to radiatefrom the center line of said block. The block 15 is provided with aperforation within which a headed metal bar. or rod 2O is held, and tothe upper and lower ends of this rod are secured the respectiveconductors 21 and 22. A screw 23 is screwed into the rod 20 from thecenter of the inner end of each shell 16 radiating from said bar,leaving its head slightly projecting, and it will thus be seen that theheads of these screws form the opposite terminals of the sockets to thatformed by the radiating shells 16. Each arm 4 is provided at its outerend with a socket 24 of the usual construction and connected to theconductor within said arm as usual, which sockets may or may not beprovided with a vswitch or cut-ofi 25, as desired. Electric IOO IZO

4, with their sockets 24. Between the lower end of the tubular casing 3and a iianged ring 26 is secured an inverted-cup-shaped piece 27, of'insulating material, and to the under side of 'this piece 27, within thecupped portion thereof, is secured a screw-threaded shell 16 similar tothose held within the perforations in the casing and above referred to.A screw 28, inserted through a perforation in the piece 27 and screwedinto the shell 16, provides means for securing a conductor 29, locatedwithin the casing 3, in electrical connection with the shell 16. Thusthe shell 16 forms a socket at the extreme lower end of the casing 3 forthe reception of the plug end of alamp or any other device usingelectricity. A screw-bolt 30, inserted through a perforation in thepiece 27 and insulated from the shell 16, has its head portion formingthe opposite electric terminal of the socket to that formed by the shell16. A nut 31 on the bolt 30 retains said bolt in place and clamps theconductor 32 into electrical contact with said bolt.

Although it is possible to connect my improved extension, as abovedescribed, to any Edison socket, it is desirable that aspeciallyconstructed socket should be used, and I have shown such asocket on the drawings in Fig. 2. This socket is the same as that whichis located at the lower end of the extension and has been describedabove in relation to Fig. 3, the only difference being in thesubstitution of a screw-threaded flanged collar 33 for the lower end ofthe tubular casing 3. In the preferred form of' socket to which theextension is to be attached the flanged collar 33 is attached to thewall, ceiling, or any other place where it is desired to have the same.A screwth readed collar 26 is screwed upon said anged v the bolt 30forms the opposite electric terminal of the'socket to that formed by theshell 16, and the nut 31 on said bolt holds the bolt in place and aconductor 35 in electric connection with said bolt.

In order to add to the appearance of my improved socket extension, asabove described, and also to add to the stability of the same whenconnected to a socket, as shown in detail in Fig. 2, I prefer to providethe upper end ofthe tubular portion 3 of the casing with a cup-shapedflange 36, which rests against the wall or ceiling when the extension isattached to the socket on the wall or ceiling and substantially as shownin Fig. 2.

The socket extension may be made with both permanently-attached ordetachably-attached arms, and I have illustrated the extension in Fig. 1as being provided with both kinds of arms.

From the above description of Figs. 1 to 5 of the drawings it will beseen that an open electric circuit may be formed within the socket orplug extension, having one terminal at the shell l and the otherterminal at the metal piece 2 of the plug end on the socket or plugextension, and that sockets may be arranged upon said extension, whichwill be in series and a part in multiple. It will also be seen thatalthough I have used different referencenumerals for the differentconductors in Figs. 2,3, 4, and 5 those shown in one view may be acontinuation of those shown in another viewas, for instance, theconductor 12 in Fig. 4 may be a continuation of the conductor 9 in Fig.2. Likewise the conductor 29 in Fig. 3 may be a continuation of theconductor 13 in Fig. 4, or the conductors 18 and 21 in Fig. 5 may berespectively continuations ofconductors 9 and 10 in Fig. 2;

The extension illustrated in Figs. 6 to 10, inclusive, is also shown asbeing provided with a plug end, by which itv may be attached to anyEdison socket. This plug end consists of the outer screw-threadedmetallic shell 1 and a central projecting metal piece 2 at the outer endof the plug end, the same as above described in relation to Figs. 1 to5, inclusive. The shell 1 and pieces 2 are insulated from each other andform the two terminals for the electric currents to be carried throughsaid plug end when connected to a suitable socket in the same manner asabove described in relation to the extension, as shown in Figs.` 1 to 5.The main body or frame of the extension (shown in Figs. 6 to 10,inclusive) is preferably made cylindrical, as shown, and is made fromsome insulating material-such as porcelain, glass, hard-rubber fiber, orsimilar insulating material. This frame of the eXtension is molded orshaped with suitable perforations, recesses, cavities, grooves,chambers, and projections arranged thereon and adapted to receive thevarious parts which constitute the device, as will be fully describedhereinafter. This frame or body 37 of the extension is provided with acavity or recess 33, which cavity is at the end of the frame opposite tothe plug end. This frame also extends into the plug end and forms theinsulation between the shell 1 and the piece 2. Two series of cavities39 39' and 40 40/ 4024O3are shown in the drawings as having fourcavities in each ninety degrees apart and arranged upon the sides of theframe 37, which cavities are preferably in two rows one above the other,the cavities in one series preferably alternating with the cavities inthe other series, so as to be able to reduce the length of the extensionas much as possible. The several cavities in the frame are connected bysuitable grooves, channels, and perforations substantially as herein-TOO IIO

after described. Within the cavity 38 is placed the washer 41, whichhasastrip 42 made in one piece with said washer and is preferablyattached to the strip 43, placed within the groove 44 and passingthrough the perforation 45 in the frame 37. The strip 43 is made in onepiece with the washer 46, placed within one otl the side cavities 39 inthe frame. A strip 47, made in one piece with the washer 46, extendsfrom said washer through the groove 48 in the frame, where itisdetachably connected to a strip 49,made in one piece with the shell 1.As the washers 41 and 46 and the strips 42, 43, 47, andv 49 are all madefrom metal, it will be seen that they will form an electric conductorfrom the shell 1 and into the cavities 39 and 38. A second washer 46 isplaced within the other cavity 39, as shown in Fig. 9, and similarconnections are made between the washer 41 in the cavity 38 and theshell 1 through the second washer 46 by means of strips 42, 43, 47, and49 similar to those above described; but only a part of this lastconnection between the cavity 38 and shell 1 has been shown, as itsconstruction is an exact duplicate oi' that shown in Figs. 7 and 9 andneeds no further illustration. Internally-serew-threaded shells 16similar to those above described in relation to Figs. 1 to 5 are placedwithin the cavities 39 39 and are riveted or otherwise irmly secured tothe washers 46 46 within said cavities. A similar shell 16 is placedwithin the cavity 38 and firmly secured to the washer 41 within saidcavity. lt will be seen that the shells 16 in the above-mentionedcavities 38 and 39 will be in electrical connection with the shell 1 ofthe plug end and will each constitute one pole of the socket `formedwithin each et' said cavities. fithin the cavity 38 is a screw 30, whichis insulated from the washer 41 and its attached shell 16, substantiallyas shown, either by an independent washer 50 or by having projection onthe frame 37 made in the same shape as the washer 50. r1`he screw 30 isscrewed into a strip 51, placed within a perforation 52 and a groove 53in the iframe 37, as shown in Fig. 7. A washer 54, preferably made inone piece with the strip 51, is placed within one of the cavities 39, asshown in said Fig. 7. A strip 55, made in one piece with the washer 54,is placed within a chamber 56 in the frame 37 and. is held in its properplace within said chamber by means of a screw-headed pin 57, whichenters a similar-shaped recess in the frame 37, or said strip may beheld in place by any other suitable and well-known means. r[he centralmetal piece 2 of the plug end at the upper end of the frame 37 is madein the form of a head on the rod 58, the lower end of which is screwedin the metal block 59, located within the chamber 56 directly above, butseparated from the strip 55. A second washer 54 is placed within theother cavity 39 and has similar integral strips 51 and 55 placed withinasimilar perforation 52, groove 53, and the chamber 56, this secondstrip 55 being held in place within the chamber 56 by the samescrew-headed spike or pin 57 and the screw 30 being attached to bothstrips 51. Internally-screw-threaded shells 16 similar to these abovedescribed are placed within the cavities 39 and 39 and are secured tothe washers 54 54 within said cavities by rivets or by any otherequivalent means. It will thus be seen that the screw 36, the strips 51,washers 54, the strips 55, the block 59, and' rod 58 form electricconductors between the central electric terminal in the cavity 38 andthe metal pieces 2, forming a central terminal on the plug end of. theextension, which conductors are only broken between the block 59 andstrips 55 within the chamber 56, and that the shells 16 in the cavities39 39 will be in electrical connection with the electric conductorspassing through said cavities. Within the chamber 56 is placed asuitably-shaped switch-lever 60, which may be turned upon its fulcrum 61so that portions thereof will contact with the strips 55 or with thescrew 57 holding them and also with the block 59. Thus when the lever isturned into contact with the strips 55 and the block 59 an unbrokenelectric conductor is formed between the screw 30, which forms theopposite pole to the shell 16 of the socket in the cavity 38, and themetal piece 2, which forms the opposite pole to the shell 1 of the plugend on the opposite end of the socket extension to that of the cavity38, which electric conductor can be broken at any time when desired bythe operation of the switch-lever 60, which has a handle 62 of anysuitable shape projecting outside the casing of the extension, as shownin Fig. 6. From the above description it will be seen as the shell 1,forming one pole of the plug end, is in electrical connection with theshell 16, forming one pole of the socket formed in the cavity 38, and asthe opposite pole 2 of the plug end is in electrical connection withtheopposite pole 30 of the socket formed in the cavity 38 that the electriclamp or other device connected to the socket in said cavity 38 willcomplete the circuit through said socket. A metal bar 63 is placedwithin a perforation 64 in the frame 37, and screws 65 65 and 65 65 arescrewed into the bar 63 from the'centers of the respective cavities 3939 and 39 39. l These screws form electric terminais of the sockets tobe formed within the respective cavities 39 and 39 to the terminalsformed by the shells 16 within said cavities, and it will be seen thatthese screws are in electric connection with each other through the bar63 and are insulated from other parts of the extension by means of theframe 37 and insulating-washers 66, placed upon each screw. As theshells 16, forming one terminal of the sockets to be formed in thecavities 39, are in electric connection with the IOO IIO

shell 1, forming one terminal of the plug end, and as the shells 16,forming one terminal of the socket to be formed in the cavities 39', arein electric connection with the metal piece 2, forming the otherterminal of the plug end, and also as the screws 65 and 65', forming theopposite terminals in the sockets to be formed in the respectivecavities 39 and 39, it will be seen that by introducing a lamp or otherelectric device, and thus forming an electric connection between theshell 16, forming the terminal in either of the cavities 39 with thescrew 65, forming the other terminal of the socket in the cavity, therewill be no closing of the electric connection between the shell 1 andthe metal piece 2, which is the opposite terminal of the plug endthrough said lamp or other device, but that it will be necessary for alamp or other device to be introduced within the socket in either of thecavities 39, thus forming an electric connection between the shell 16and the screw 65' in said cavity in order to complete the circuitbetween the two terminals of the plug end, and therefore the lamps orother device in the cavities 39 and 39 will be arranged in series andthat there will be as many series of lamps or other devices as thegreatest number of cavities 39 or 39 used on the extension. By thismeans I am able to use lamps or other electric `devices which presentdifferent degrees of resistance to a current of electricity in thedifferent sockets on the extension, those used in the socket in thecavity 38 being of greater resistance than those used in the sockets inthe cavities 39 and 39. When the same current is desired, the sum of theresistances 39 and 39 is equal to the resistance in 38.

Referring to Fig. 10 of the drawings, in which the arrangement of theconductors leading .to and from the series of cavities 40, 40', 402, and403, and the construction of the sockets within said cavities are moreclearly shown, and also referring to Figs. 7 and 8 of the drawings for afurther illustration of the same, within the cavity 40 is placed asheet-metal washer 67, similar in construction to that of the washers41, 46, and 54 in the cavities 38, 39, and 39. This washer is connectedto the metal strip 43 by means of a thin metal strip 68, made in onepiece with the washer 67 or attached thereto and inserted through aperforation 69 in the frame or body of the eX- tension. To the washer 67is secured a shell 16, similar to those within the other cavities abovementioned. It will thus be seen that the shell 16 within the cavity 40is in electric connection with the shell 1 of the plug end through thewasher 67, the metal strips 68 and 43, the washer 46, and the metalstrips'47 and 49, and forms one terminal of the socket to be formed insaid cavity. Within the cavity 40 is placed a washer 70, to which ashell 16 is firmly attached, and this washer is provided with a metalstrip 71, made in one piece therewith or attached thereto, which metalstrip is inserted within a recess 72 in the frame or body of theextension and has la screw 73 screwed into said strip from the center ofthe bottom of the cavity 40. The head 74 of the screw 73 forms theopposite terminal oi' the socket in the cavity 40 to that of the shell16 in said cavity, while the shell 16 in the cavity 40 forms oneterminal of the socket to be formed in said cavity 40, and it will beseen that these/two terminals in the cavities 40 and 40 are in electricconnection with each other, but are insulated from other parts by theframe or body 37 of insulating material. Within the cavity 403 isarranged a washer 75, with a shell 16 attached thereto, said washerhaving a metal strip 76 made in one piece with said washer and passingthrough a perforation 77 in the frame 37, where it is attached to thestrip 51 in a similar' manner to the washer 67, shell 16, and strip 68within the cavity 40, and it will be seen that this shell 16 in thecavity 403 is in electrical connection with the metal piece 2 of theplug end through the washer 75, the strips 76 and 51, the washer 54, thestrip 55, the switch-lever 60, the block 59, and rod 58 when theswitch-lever is turned so as to contact with the strip 55 and the block59, and it will also 'be seen that the shell 16 within the cavity 403forms one terminal of the socket to be formed within said cavity 403.Within the cavity 402 is placed a washer 78, with a shell 16 firmlyattached thereto, said washer having a metal strip 79 made in one piecetherewith or firmly attached thereto,which metal piece is insertedwithin a recess 80 in the frame or body 37 and receives a screw 81,screwed into said strip from the center of the cavity 403, the head 82of said screw forming an opposite terminal ofthe socket formed in thecavity 403 to that of the shell 16 within said cavity 40", while theshell 16 within the cavity 402 forms one terminal of the socket to beformed within the cavity 402, and it will also be seen that the shell 16in the cavity 402 is in electric connection with the head 82 of thescrew in the cavity 403 in a manner similar to the washer 70, the shell16, the metal strip71, the recess 72, and the screw described inrelation to the cavity 40. A rod 83 is inserted through a perforation 84in the frame or body 37 of the extension and has its head 85 located inthe center of the cavity 40 and forming an opposite terminal of thesocket to be formed in the cavity 40 to that formed by the shell 16within said cavity. The rod 83 has a nut 86 thereon,which nut is locatedin the center of the bottom of the cavity 402 and forms the oppositeterminal of the socket to be formed within said cavity 402 to thatformed by the shell 16 within said cavity.

From the above description it will be seen that one terminal of eachsocket to be formed within each cavity 40, 40', 402, and 403 is in TCOTIO

'electric connection to one terminal'of the socket to be formed withinone of the other of-said cavities, that the terminals so connected areinsulated from other metalic parts of the device, and that the shells inthere- Iminals of the plug end and through any of the devices insertedwithin said cavities. By'

the construction of the conductors `between the tern'iinals of thesocket formed in the cavities 40, 40', 402, and 403 it will be seen thatlamps or other devices connected to said sock- \ets will be arranged inseries and that itwill require the insertion of a suitable plug end inall of said sockets before acurrent of electricity will How through anyof said sockets. and consequently electric devices presenting differentresistances to the iiow of the current may be used in said sockets.

It will be understood that when a single lamp of low resistance isdesired to be used it may be connected to the socket in either of thecavities 40, 40', 402, or 403, and in order to complete the circuitthrough said lamp I will place plugs in each of the sockets formed inthe other cavities, which plugs will themselves contain suiiicientresisting power to the iiow of a current of electricity to properlycontrol said current of electricity.

By the use of the socket extension, as shown in Figs. 6 to 10,inclusive, I am able to use upon the same extension lamps or otherelectric devices having various degrees of resistance and can use themall at the same time or singly, as desired. I may also have the initialcurrent of a high potential and reduce the potential the necessaryamount by the introv duction of plugs in the other sockets, which plugswill be of such a resistance as to leave the necessary potential for thelamp or other device desired to be used.

In some cases it is necessary for two or even more of my improvedextensions of different arrangements to be coupled together and be usedin order to adapt the same so as to be attached to either a socket orplug' or toa socket or plug' of a different make either on the lamp orother device or on the feed-wire which supplies the current ofelectricity. In Fig. 10 I have illustrated two of my improved extensionsof different arrangements coupled together, so as to adapt an extensionhaving Edison plugs and sockets to a Thomson- Houston socket on afeed-wire or so that a lamp or other electric device having' aThomson-Houston socket can be attached to a socket or plug extensionprovided with Edison sockets. In this second extension the main body 87,of suitable insulating material, has a shell 1 and a metal pin 2 at oneend of-said body similar to the other extension, above described, andwhich form the opposite termig nals of an Edison plug end. rIhe oppositeend of the body 87 has a washer 88 on they -The washer 88 and thc shell1 on opposite ends of the body 87 are in electrical connection with eachother by means of the screw or screwthreaded rod 92. The metal piece Qismade on the end of a screw-threaded rod 93,r4 which passes through aperforation in the body 87 and is screwed into the metal piece 89 at theoppo" site end of said body. It will thus be seen that this rod 93 formsa metal connection between the metal pieces 2 and 89. By the use of thisarrangement of my extension with or 4without a second extension it willbe seen that I am able to attach lamps or other electric devices havingEdison or rIhomsoirHouston plugs or sockets to a socket on a feed-wire,which socket is of either construction. It will be also understood thatI am not confined to forming this arrangement of my extension with anEdison and Thomson-Houston plug end at opposite ends thereof, but that Imay form the same with other and well-known constructions of plug ends,according to the requirements.

Referring to the arrangement of my inven. tion as illustrated in Figs.11 to 14, inclusive. the body portion of the extension is provided atits end opposite to the plug end with a cavity 38, and the side of saidbody portion is provided with one or more cavities similar to thosedescribed in relation to Figs. 6 to 10. The end cavity 38 and the sidecavities 39 are connected by grooves or channels 94, and similar groovesor channels 95 extend from the side cavities 39 toward and to the plugend 1 on the extension. A thin metal strip or plate 96 (shown in Fig.21) is so shaped and bent that washer-shaped portions of it will rest atthe bottom of each cavity 38 and 39, while connecting portions will restwithin the grooves or channels 94 and 95. The shell 1 of the plug' endis formed with projecting' ears, which extend into the grooves orchannels 95 and are connected in any suitable manner to the portions ofthe plate 96 restingin said grooves or channels. On the drawings thisconnection is formed by means of suitable screws or rivets 97. Theportions of the plate 96 which rest within the cavities 38 and 39 arepreferably made inring form, leaving a central perforation thereinasshown in Fig. 21, for a purpose to be understood by the completedescription of the device. Thin metal shells 16 IOO IIO

16 are inserted within the cavities 38 and 39 and are riveted orotherwise secured to the plate or strip 96. These shells are preferablyattached to the plate or strip 96 prior to inserting said plate withinthe cavities and channels. As the shell 1 of the plug end is attached tothe plate or strip 96 and as the shells 16 are also attached to saidplate, it will be seen that all of said parts are in electrical contactwith each other and together form an electric conductor for a current ofelectricity having a terminal at the shell 1 and also at each socket 16to connect with terminals of branch circuits to be connected at saidplaces to said conductor. Tithin a central perforation 98 in the frameof the extension is placed a threaded metal bar or rod 99, the Lipper orthreaded end of which forms the terminal 2 of the plug end, while theopposite or lower end thereof is provided with a screw 100, whichprojects into or through the perforations in the plate 96 and forms theterminal of the branch circuit, the opposite terminal of which is formedby the shell within the cavity at the end of the frame. Branchperforations 101 are formed in the frame of the extension, which branchperforations extend from the perforation 98 to the center of each of thecavities 39, and within each of these branch perforations is a headedbranch rod 102, the :inner ends of said bars being attached to or inelectrical connection with the central bar or rod 99, and the outerheaded ends of said branch rods or bars projecting into or through thecentral perforation in the plate 96 within the cavities 39, where theyform the opposite terminals of the sockets to be formed in said cavitiesto that formed by the shell 16 within said cavities. The frame of theextension is preferably provided with a protecting outer casing 103,made of metal or other suitable material, which outer casing isinsulated from the shell 1 of the plug end, also from the shells 16within the cavities 38 and 39. This outer casing is made in sections,which are secured together by screws or other devices when said casingis in place. The outer casing is provided with perforations coincidingwith but preferably larger than the cavities 38 and 39, thus admittingof the insertion of a plug end of a lamp or other article into socketscontained within said cavities without contacting with the outer casing.

By the use of my extension, as above described, it will be seen that aplurality of lamps or other articles having plug ends with oppositeterminals thereon may be attached to a socket which was originallydesigned to receive one article only, that the several articles whichmay be attached to the sockets formed therein will be arranged inmultiple, and that any one or more of the sockets may be used, as isdesired.

Thus far I have described my plug and socket extension, in which socketswith two terminals or poles are formed; but it is equally adapted forsockets with one terminal or pole only. I have also shown and thus fardescribed the plugs and sockets as being connected by a screw-threadedjoint; but sockets and plugs which are to be connected in other ways maybe used in my invention without departing from the spirit thereof, and Ihave shown socket and plug with a single terminal and adapted to beconnected in another way than by a screw-threaded joint in Figs. 15 to20. In this construction of my invention I prefer to provide theeXtension'with a plug end arranged and constructed as described inrelation to the other views of the drawings, the same having anexternally-screw-threaded shell 1 and a metal piece 2, made in the formof a head on the bolt 58. I also provide thc extension with a cavity 38at the end opposite to the plug end and introduce aninternally-screw-threaded shell 16 within said cavity and a screw 30,the shell 16 and screw 30 forming the opposite terminals of the socketformed in the cavity 38. Vithin vertical perforations in the body orframe 104 of the extension are placed the metal rods or bars 105 and106. The upper end of the rod 105 is connected to a metal piece 107 onthe shell 1 of the plug end by means of the screw 108 or equivalentdevice. The lower end of the rod 105 is in electrical connection withthe metal piece 109, attached to or made in one piece with the shell 16in the cavity 38 by means of the screw 110 or equivalent means. It willthus be seen that the shells 1 and 16 are in electric connection witheach other through the rod 105. To the upper end of the rod 106 isconnected the metal plate 111, which is placed within a horizontalrecess in the frame of the extension and into which the screw-threadedend of the rod 58 is screwed. The screw 30 is screwed into one end ofthe metal plate 112, which is placed within a horizontal recess in theframe of the extension and has its opposite end attached to the rod 106.It will thus be seen that the metal piece 2 is in electric connectionwith the screw 30. Thus the socket in the cavity 38 has two terminals,and if a lamp or other device using electricity should be connected tothe socket in said cavity said lamp would be lighted. The frame of theextension is provided with two series of recesses or cavities 113 and114, which extend horizontally from the exterior of the frame toward therespective rods 105 and 106. These cavities are preferably arranged sothat they radiate in horizontal planes with the centers of the rods 105and 106 as the centers of radiation for the two series of cavities.Within the cavities 113 and 114 are placed the respective metal shells115 and 116, which are secured to the respective rods 105 and 106, andthese shells are split longitudinally, so that they will formspring-sockets and will retain a plug 117 in contact therewith by fric-IOO tion alone. As the shells 115 and 116 are each in connection withbut one of the rods 105 or 10G, it will be seen that each of the socketsformed by said shells will be a singlepole-socket, those being connectedto the rod 105 being of one polarity, while thoseconnected to the rod106 are of an opposite polarity, and that it will be necessary tointroduce a plug end into one of the shells connected to each of therods 105 and 106 in order to complete a circuit. rIhe preferred form ofshells and plug ends to be used in this construction of my improvedsocket and plug extension have been shown in detail in Figs. 17 to 20,inclusive, the construction of the shell having been described and thatof the plug end consisting' of a straight piece of metal 117, whichsubstantially iits the interior of the shell,being slightly larger thanthe interior of the shell, so as to cause sufficient friction to keepthe plug within the shell.

Having thus fully described the nature,con struction, and operation ofmy invention, I wish to secure by Letters Patent and claimH 1. In anextension to'an electric coupling, a frame or body with cavities andprojections forming respectively a plurality of socket portions and aplurality of plug portions of a plurality of electric couplings thereon,a metal shell and a metal piece, insulated from each other, arrangedwithin each cavity and on each projection constituting oppositeterminals of a socket or plug formed in said cavity and on saidprojection, and electric conductors within said frame or bodypermanently connecting a terminal of one socket or plug' with a terminalof another socket or plug, whereby each part of an electric couplingcontained on the said frame will be within an electric circuit and readyto receive the other part of the coupling, in order to couple anelectrically-operated device thereto and to supply it with electricity,for the purpose set forth.

2. In an extension to an electric coupling, a frame or body withprojections formingplug portions of electric couplings thereon, twometal pieces on each projection insulated from each other formingelectric terminals thereon, and electric conductors within said body orframe permanently connecting each terminal on each projection with aterminal von another projection, whereby each part of an electriccoupling contained on the said frame will be within an electric circuitand ready to receive the other part of the coupling', in order to couplean electrically-operated device thereto and to supply it withelectricity, for the purpose set forth.

3. In an extension to an electric coupling, a frame or body withcavities forming socket portions of electric couplings therein, twometal pieces in each cavity insulated from each other forming electricterminals therein, and electric conductors within said body or framepermanently connecting each terminal in each cavity with aterminal inanother cavity, whereby each part of an electric coupling contained onthe said frame will be within an electric circuit and ready to receivethe other part of the coupling, in order to couple anelectrically-operated device thereto and to supply it with electricity,for the purpose set forth.

4. In an extension to an electric coupling, a frame or body withcavities and projections thereon, two metal pieces `in each cavity andon each projection insulated from each other and forming oppositeelectric terminals, electric conductors within said body or framepermanently connecting each terminal of each cavity or projection with aterminal in another cavity or projection combined with detachable armshaving a plug and socket thereon to engage the terminals in each of saidcavitics or on each of said projections, whereby a self-containedcomplete and portable chandelier with detachable and interchangable armsis formed, for the purpose set forth.

5. In an extension to an electric coupling, a body or fratrie, withgrooves, projections and cavities thereon, a screw-threaded metal shellin each cavity and on each projection forming an electric terminal, acentral metal piece in each cavity and on each projection forming anopposite terminal to those formed by the metal shell, metal washers insaid cavities to which the metal shells are attached, and metal stripswithin said grooves connecting said washers, forming electric conductorswithin the body of the extension and holding the metal shells withinsaid cavities, for the purpose set forth.

6. In an extension to an electric coupling, a body or frame withgrooves, projections and cavities thereon, metal shells and centralmetal pieces forming electric terminals, and conductors within saidframe connecting a part of said terminals in series and a part of saidterminals in parallel, whereby electric devices of various resistancesmay be connected to the same extension, for the purpose set forth.

7. In-an extension to an electric coupling, a body or frame withgrooves, projections and cavities thereon, metal shells and centralmetal pieces forming electric terminals, and conductors within saidframe connecting said terminals in combined series, multiple andmultiple series, for the purpose set forth.

8. In an extension to an electric coupling, a body or frame, aprojection on one end, a metal shell and a central `metal piece on saidprojections forming electric terminals thereon; a cavity in the oppositeend of the frame of the extension, a metal shell and a central metalpiece within said cavity forming electric terminals in said cavity; andconductors within said frame connecting the terminals on said projectionwith those in said cavity;

IOO

IIO

series of cavities on the sides of said frame, a vices be connected tothe terminals in the IO metal shell and a central metal piece withinseveral cavities, for the purpose set forth.

each side cavity forming electric terminals In testimony whereof l haveatlixed my sigtherein; and conductors withindthe frame conci nature inpresence oi' two witnesses.

nectino the terminals in the si e cavities an f the teiaminals onV theprojection, whereby the WVILLIAM H KELSEX' terminals on the projectionmay be connected Witnesses:

with the terminals of a source of electricity HENRY CHADBOURN,

and the terminals on electrically-operated de- ARTHUR C. JONES.

